Use of a fiber conduit contactor for extraction

ABSTRACT

Processes are provided which utilize fiber conduit reactors/contactors to effect extraction from a fluid stream, particularly a fermentation broth, a waste stream of a fermentation process, a fluid comprising a dye, or a fluid comprising a pharmaceutical compound. In particular, methods are provided which include introducing a first stream comprising an extractant and a second stream which is substantially immiscible with the first stream into a conduit reactor proximate a plurality of fibers. The streams are introduced into the conduit reactor such that they are in contact with each other and the extractant of the first stream interacts with the second stream to extract a fermentation product, a fermentation byproduct, a dye or a pharmaceutical compound from the second stream into the first stream. The method further includes receiving the first and second streams in collection vessel/s and withdrawing separately the first and second streams from collection vessel/s.

PRIORITY CLAIM

This application is a continuation of pending U.S. patent applicationSer. No. 14/030,760 filed on Sep. 13, 2013, which claims priority toU.S. Provisional Application No. 61/702,345 filed Sep. 18, 2012.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention generally relates to fiber conduit reactors/contactors,and specifically relates to processes utilizing such devices to effectextraction from fluidic streams.

2. Description of the Related Art

The following descriptions and examples are not admitted to be prior artby virtue of their inclusion within this section.

Chemical extraction is desirable for a variety of reasons. Inparticular, many solids, liquids and gases contain contaminants whichmay hinder their further use and, thus, extraction of the contaminantsis desirable. In addition or alternatively, many solids, liquids andgases contain valuable substances which are desirable to extract.Moreover, waste streams often contain pollutants which do not meetenvironmental regulations. As such, considerable effort and expense isoften undertaken to remove the chemical species from fluidic streams andsolids. Examples of chemical species that are often extracted from fluidstreams and solids include but are not limited to dyes, acids, bases,phenolics, amines, sulfur compounds, solvents, catalysts, drugs, andheavy metals, etc. As a particular example, hydrodesulfurization isoften used to desulfurize petroleum streams contaminated with sulfurcontaining compounds, but the process is relatively expensive anddangerous as it is conducted at high temperatures and pressures.

One manner of chemical extraction involves dispersions of one fluidicphase in another to generate small droplets with a large surface areawhere mass transfer and reaction can occur. In cases of solventextraction, one or more chemical agents are used to break down thecomponents within a substance to enable extraction. Those materialswhich are more soluble or react more readily to a particular acid orbase get separated from the rest. The separated materials are thenremoved, and the process begins all over again with the introduction ofmore chemicals to leach out more components. In any case, the timerequired for solvent extraction can vary widely. In particular, somematerials need to be allowed to mix and sit for a long period of timefor the components to separate out. Complicating things further is thatmany of the chemicals used as well as some by-products of solventextraction are extremely hazardous and must be handled and disposed ofwith great care.

A common method of recovering metals from ores and concentrates is byleaching with a mineral acid. The leached liquid containing thedissolved metal, known as a pregnant leach solution, is collected andfurther processed to extract and separate the metals. By way of example,rare earth metals are generally recovered from bastnaesite by leachingthe host rock with hydrochloric acid. Uranium can be recovered fromuranium-containing host rock by leaching with phosphoric acid. Copper,beryllium, nickel, iron, lead, molybdenum, aluminum, and manganese canbe recovered from host rock by leaching with nitric acid. Copper,beryllium, nickel, iron, lead, molybdenum, aluminum, germanium, uranium,gold, silver, cobalt, and manganese can be recovered from host rock byleaching with sulfuric acid or hydrochloric acid. In hydrometallurgy,mineral concentrates are separated into usable oxides and metals throughliquid processes, including leaching, extraction, stripping, andprecipitation. By these means, the elements are dissolved and purifiedinto leach solutions. The metal or one of its pure compounds (such as anoxide) is then precipitated from the leach solution by chemical orelectrolytic means. In stripping, the metal in the organic solution isstripped (extracted) by an acidic solution to form a loaded strip liquor(loaded electrolyte), resulting in a much purer metal solution. If thevolume of the strip solution is much smaller than that of the organicsolution, metal is also concentrated.

Mining metal compounds is relatively simple, but extracting individualelements from the ore can sometimes be difficult. For example,processing of rare earth elements and metals of the precious metal groupand the uranium group as well as many other metals often requires dozensof procedures each resulting in minute changes in the complex stream. Inmany cases the procedures need to be repeated, and thus, separating andextracting a single metal element, especially one of the heavy metalelements, takes a great deal of time, effort and expertise. Furthermore,the complex metallurgical technologies have taken decades to evolve, andeach metal element presents its own unique challenges for separating andextracting. As a result, it can take many years for scientists to crackthe geological code and design appropriate metallurgic processes foreach metal element stream.

A common method of recovering volatile products from solutions involvesdistillation of the product from the solution. For instance, alcoholsare often produced by fermentation and recovered by energy intensivedistillation. Another method of recovering chemicals from aqueous orother production streams involves adsorption and desorption from solids,but such processes are often laborious, expensive, and/or produceundesirable waste. For example, pollutants from effluent air streams arefrequently processed using solid adsorbants. Another example isadjusting a fermentation broth containing valuable pharmaceuticalproduct through a series of pH changes, passing it through either asilica or a polymeric chromatography packing, and subsequently usingreverse phase column chromatography to produce products from anadsorbent resin. After repeating the process a salt of the product iscrystallized with a solvent and the crystals are neutralized and theproduct is precipitated in an organic solvent such as acetone or alcoholto produce pure product.

An undesirable byproduct of many extraction processes is the formationof a gelatinous emulsion of chemical phases (often organic and aqueousphases) known as crud, gunk, grungies, grumos, or a rag layer. Problemscan occur as the amount of crud builds up in the system, particularlyhindering a system's ability to reduce operational costs and in cases ofexcessive crud formation (or poor crud management), crud can also impactproduction. Since it is difficult to avoid the formation of crud, mostoperations have systems for removing it. A further disadvantage of theformation of crud is that once it is removed from a system it must betreated so that the solvent used to extract the noted chemical can berecovered. Techniques vary at different operations, but all include somebasic physical force used to separate the solid and liquid phases ofcrud, such as a centrifuge, filter press, or agitated tank. Whenchoosing a treatment method, one has to consider the economicsassociated with stopping production to remove crud, as opposed toprocessing the crud while the plant is in operation.

Accordingly, it would be desirable to develop different systems andmethods for efficiently and cost-effectively extracting chemicals fromfluids and solids, particularly systems and methods of reducedcomplexity and which minimize waste.

SUMMARY OF THE INVENTION

Processes are provided which utilize fiber conduit reactors/contactorsto effect extraction from a fluid stream, particularly a fermentationbroth, a waste stream of a fermentation process, a fluid comprising adye, or a fluid comprising a pharmaceutical compound. In particular,methods are provided which include introducing a first stream comprisingan extractant proximate a plurality of fibers positioned within aconduit reactor and extending proximate to one or more collectionvessels. The method further includes introducing a second stream intothe conduit reactor proximate to the plurality of fibers, wherein thesecond stream is in contact with and is substantially immiscible withthe first stream. The first stream and the second stream are introducedinto the conduit reactor such that the extractant of the first streaminteracts with the second stream to extract a fermentation product, afermentation byproduct, a dye or a pharmaceutical compound from thesecond stream into the first stream. The method further includesreceiving the first and second streams in the one or more collectionvessels and withdrawing separately the first and second streams from theone or more collection vessels.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present invention, and theadvantages thereof, reference is now made to the following descriptionstaken in conjunction with the accompanying drawings, in which:

FIG. 1 illustrates an example of a fiber conduit contactor useful forthe processes described herein;

FIG. 2 illustrates an example of another fiber conduit contactor usefulfor the processes described herein;

FIG. 3 depicts an example of a fiber conduit contactor system useful forthe processes described herein; and

FIG. 4 depicts a shell and tube heat exchanger for incorporation into afiber conduit contactor.

While the invention is susceptible to various modifications andalternative forms, specific embodiments thereof are shown by way ofexample in the drawings and will herein be described in detail. Itshould be understood, however, that the drawings and detaileddescription thereto are not intended to limit the invention to theparticular form disclosed, but on the contrary, the intention is tocover all modifications, equivalents and alternatives falling within thespirit and scope of the present invention as defined by the appendedclaims.

DETAILED DESCRIPTION OF THE INVENTION

The disclosure herein relates generally to fiber conduitreactors/contactors, and specifically to processes utilizing suchdevices to effect separation and reaction between two immisciblereaction components using catalysts, solvents, and/or co-solvents. Morespecifically, the disclosure herein is directed to new and improvedprocesses for extraction of chemical compounds and/or chemical elementsof a first fluid by component(s) of a second, substantially immisciblefluid in a fiber conduit reactor/contactor. Applications of particularinterest include extraction of metal compounds and metal elements fromfluid streams, but extraction of various metalloid and non-metalcompounds as well as various metalloid and non-metal elements from fluidstreams are disclosed as well. As used herein, the term “element” refersto a substance consisting of only one type of atom. In contrast, theterm “compound,” as used herein, refers to a material formed from two ormore different elements that are chemically combined (i.e., the atomsare held together by chemical bonds) in definite proportions by mass.Both elements and compounds are categorized herein as “pure chemicalsubstances” in that they cannot be broken down into individualcomponents by a physical change. This categorization differs from thatof a “chemical mixture,” which is referred to herein as a combination oftwo or more pure chemical substances that can be separated by a physicalchange (i.e., the pure chemical substances of a mixture are not combinedby chemical bonds).

As set forth in more detail below, the processes described herein may beparticularly applicable for processes associated with mining. Otherapplications, however, are disclosed as well, including but not limitedto processes used to produce a concentrated or purified product in oneof the process streams. For example, applications of the processesdescribed herein may alternatively include extraction of metal elementsor metal compounds from manufacturing, refinery or waste streams ofprocesses other than those associated with mining. Yet otherapplications may include extraction of fermentation products orbyproducts from manufacturing or waste streams, such as for exampleextraction of alcohols or acids from fermentation broths or fermentationwaste streams. In some cases, applications of the processes disclosedherein may include removing pollutants, contaminants, and/or impuritiesfrom process or waste streams, such as but not limited to extractingorganosulfur compounds from petroleum streams or extracting diacetin,monoacetin and/or glycerol from biodiesel-triacetin mixtures.Furthermore, processes for extracting dyes from fluid streams andprocesses for extracting pollutants from gas streams, such as sulfurcompounds, CO₂, CO, NO_(x) from air or natural gas, are provided.

Applications are also disclosed involving the extraction ofneutraceutical compounds and/or elements (e.g., ib and/or minerals) fromfluid streams and the extraction of pharmaceutical compounds (e.g.,ibuprofen or antibiotics (such as Trimethoprim) from production fluids(a.k.a., manufacturing broths)). Another process described herein whichmay be particularly applicable but is not necessarily limited to thepharmaceutical field is the extraction of enantiopure compounds from afluid stream. In some embodiments, the extraction processes describedherein may be used to separate water soluble entities from aqueous acidor aqueous alcohol manufacturing or refinery product streams (e.g.,streams containing ethanol, butanol, acetic acid, lactic acid, pyruvicacid, picolinic acid, 1,2-propanediol, and the like) or vice versa todehydrate them without distillation. In further embodiments, theextraction processes may be used to extract solvents and/or catalystsfrom a fluid stream. Other applications may be suitable as well.

As noted above, extraction processes may be conducted in a fiber conduitreactor to extract metals from fluids, such as leachates or otherfluids. Examples of metals which may be extracted from fluids includealkali metals (i.e., lithium, sodium, potassium, rubidium, cesium, andfrancium); alkaline earth metals (i.e., beryllium, magnesium, calcium,strontium, barium, and radium); transition metals (i.e., zinc,molybdenum, cadmium, scandium, titanium, vanadium, chromium, manganese,iron, cobalt, nickel, copper, yttrium, zirconium, niobium, technetium,ruthenium, rhodium, palladium, silver, hafnium, tantalum, tungsten,rhenium, osmium, iridium, platinum, gold, mercury, rutherfordium,dubnium, seaborgium, bohrium, hassium, and copernicium); post-transitionmetals (i.e., aluminum, gallium, indium, tin, thallium, lead, bismuth,and polonium); lanthanides (i.e., lanthanum, cerium, praseodymium,neodymium, promethium, samarium, europium, gadolinium, terbium,dysprosium, holmium, erbium, thulium, ytterbium, and lutetium);actinides (i.e., actinium, thorium, protactinium, uranium, neptunium,plutonium, americium, curium, berkelium, californium, einsteinium,fermium, mendelevium, nobelium, and lawrencium); elements which arepossibly metals (e.g., meitnerium, darmstadtium, roentgenium, ununtrium,flerovium, ununpentium, and livermorium); and elements which aresometimes considered metals (i.e., metalloids, e.g., germanium, arsenic,antimony, and astatine). It is noted that other classification of metalgroups may be considered for the processes described herein. Forexample, the processes described herein may be used to extract preciousmetals (e.g., platinum, rhodium, gold, iridium, osmium, palladium,rhenium, ruthenium or silver).

In some cases, the extraction processes described herein (i.e.,processing through a fiber conduit reactor) may be particularly suitedto extracting rare earth elements (REEs). In particular, because REEsare so similar in chemical behavior, they are difficult to separate fromeach other and, thus, conventional extraction methods require multiplestages to complete the extraction process. The processes describedherein, however, have a high rate of mass transfer, and, thus REEs maybe extracted out of solution faster than conventional techniques. Assuch, the processes may be used to extract one or more REEs fromstreams, including those which do not include other metals and thosewhich do. In some cases, the processes described herein may be used toextract an REE from other REEs. In addition or alternatively, othermetals may be extracted using the fiber conduit reactor describedherein.

In some cases, an extractant solution discharged from a fiber conduitreactor may include more than one metal. In such embodiments, the metalsmay be selectively recovered (scrubbed) from the extractant solution bywashing the solution with strong aqueous acids. Such a washing processmay be conducted in a fiber conduit reactor or alternatively may beconducted by another technique. In yet other cases, metals may beselectively extracted from a fluid in a single extraction pass through afiber conduit reactor by using two extraction solvents simultaneouslywithin the reactor as described in more detail below. In particular, theprocesses described herein (i.e., processes conducted through a fiberconduit reactor) may be applicable for extracting one or more metalsfrom solutions containing more than one metal. For example, theprocesses may be conducted in a fiber conduit reactor to extract copperfrom zinc; gold, silver, platinum, palladium from other metals and/orfrom each other; transuranium metals from other metals and/or eachother; heavy metals from drinking water and/or process water.

The fiber conduit apparatuses used to employ the processes describedherein may be utilized as reactors, extractors and/or contactors. Forsimplicity, the fiber conduit apparatuses considered for the processesdescribed herein are interchangeably referred to as fiber conduitcontactors, fiber conduit reactors, fiber conduit receivers, fiberconduit contactors/reactors and/or fiber conduitcontactors/reactors/receivers. It is noted that some extractionprocesses involve a chemical reaction to affect extraction while othersmay not. Embodiments of fiber conduit reactors which may be employed forthe methods discussed herein are shown and described in U.S. Pat. Nos.3,754,377; 3,758,404; 3,992,156; 4,491,565; 7,618,544; and 8,128,825,all which are incorporated herein by reference to the extent notinconsistent herewith. In general, the processes described herein employtwo essentially immiscible fluids with reactive components in them,including one phase which preferentially wets the fibers of the conduitreactor (hereinafter referred to as the “constrained phase”) and anotherphase which is passed between the fibers (hereinafter referred to as the“continuous phase”). Depending on the process employed, a catalyst,solvent or cosolvent may also be used within the fiber conduit reactor.In any case, the phases discharged from the fiber conduit reactor may beseparately withdrawn and, in some cases, either or both phases may befurther processed in the same fiber conduit reactor, a different fiberconduit reactor, or another processing apparatus, such as for washing,separation and/or further extraction.

Advantages of using a fiber conduit reactor for extracting, separating,reacting and/or contacting elements and compounds include but are notlimited to:

-   (1) Processes are very fast because of very high surface area for    mass transfer.-   (2) Faster processing allows relatively small fiber conduit reactors    to be used instead of large open settling zones and/or tanks. As a    result, the footprint of the process, the cost and size of the    process equipment, and loss of volatile organics will be less, with    significant implications for solvent recovery rates and plant    safety.-   (3) By-products are greatly reduced because dispersions and rag    layers (crud) are virtually eliminated. Since dispersions are    reduced and sometimes eliminated, settling time for coalescence of    the dispersed particles is reduced and sometimes eliminated, thus    reducing collection and processing time and costs, which give way to    an even smaller plant foot print.-   (4) The conduit reactor is an extremely effective microchannel    extractor/reactor/contactor with the additional benefit of being    easily scaled up to any desired volume by simply using larger    diameter conduits with more fibers. This is in stark contrast to    other traditional “scale-up” approaches, where larger volumes can    impact the physical processes and efficiencies involved.

As previously mentioned, an undesirable byproduct of many extractionprocesses, particularly bulk processing, is the formation of agelatinous emulsion of chemical phases (often organic and aqueousphases) known as crud, gunk, grungies, grumos, or a rag layer. Ingeneral, crud is formed by the diffusion of particles, particularlynanoparticles, into the liquid-liquid interface of the two immiscibleliquids used in the extraction process. The behavior of nanoparticles inprocesses performed in a fiber conduit reactor, however, differs greatlyfrom processes performed in bulk processing. The main difference betweenthe two methods is the type of flow. In bulk processing, the turbulentmixing of the two phases promotes transport of particles to theliquid-liquid interface. In contrast, free phase flow in the fiberconduit reactor is laminar so that transport of particles to theliquid-liquid interface is much slower, often slower than the diffusion,complexation and extraction rates of ions at the liquid-liquidinterface. For example, the typical diffusion time of metal ions to aliquid-liquid interface via solvent extraction is about 6 seconds andthen the complexation and extraction of the metal ions takes aboutanother minute to reach equilibrium. In contrast, the diffusion time ofsilica particles in solution, for example, is typically more than onehour (i.e., depending on the viscosity and fluid dynamics of thesolution as well as particle size). Thus, if the contact time betweenimmiscible liquids in a fiber conduit contactor/reactor is designed tobe shorter than the characteristic diffusion time of particles in theliquids, the crud problem in a fiber conduit contactor/reactor may beavoided.

The fibers employed in a fiber conduit reactor for the extractionprocesses described herein may, in some cases, be longitudinal andextend substantially parallel to the sidewalls of the reactor conduit.Other fiber configurations, however, may be considered. In particular,in some embodiments, the fibers may be arranged off angle relative tothe conduit sidewalls (i.e., not parallel) (e.g., the fibers may extendfrom an off-center location at top of the pipe to the bottom center orto a bottom opposing sidewall or vice versa, etc.). In addition oralternatively, the fibers may be crimped (i.e., zig zag), spiral wound,and/or intertwined (e.g., similar to steel wool cleaning pads stuffed ina pipe). In some embodiments, the fibers may have a circularcross-section, but other cross-sectional shapes may be considered, suchas but not limited to elliptical, triangular, square, rectangular,dog-bone, bean-shaped, multi-lobular, and polygonal. In some cases, thefibers may be scaled or serrated. In other embodiments, the exteriorsurfaces of the fibers may be smooth. In some cases, the fibers can bethreads made of relatively short fibers twisted together. In otherembodiments, the fibers may be configured similar to a treelikestructure with a main fiber and various size limbs and branches attachedto the main trunk. Multifilament fibers (textile threads) and lesssymmetrical monofilaments have greater possibility for dispersionscreated in the exiting free phase, so it would be preferable to usesymmetrical monofilament fibers, but reaction/extraction still occursusing multifilament non-symmetrical fibers and the resulting dispersionmay be generally manageable in practice. In any case, the configurationof the fibers (e.g., shape, size, number of filaments comprising afiber, symmetry, asymmetry, etc.) within a conduit reactor may be thesame or different for the processes described herein.

The material of fibers for the extraction processes described herein maybe, but are not limited to, cotton, jute, silk, treated or untreatedminerals, metals, metal alloys, treated and untreated carbon allotropes,polymers, polymer blends, polymer composites, nanoparticle reinforcedpolymer, combinations thereof, and coated fibers thereof for corrosionresistance or chemical activity. In general, the fiber type is selectedto match the desired constrained phase. For example, organophilic fibersmay be used with a constrained phase that is substantially organic. Thisarrangement can, for example, be used to extract organic materials fromwater with organic liquids constrained to the fibers. Suitable treatedor untreated minerals include, but are not limited to, glass, alkaliresistant glass, E-CR glass, quartz, asbestos, ceramic, basalt,combinations thereof, and coated fibers thereof for corrosion resistanceor chemical activity. Suitable metals include, but are not limited to,iron, steel, stainless steel, nickel, copper, brass, lead, thallium,bismuth, indium, tin, zinc, cobalt, titanium, tungsten, nichrome,zirconium, chromium, vanadium, manganese, molybdenum, cadmium, tantalum,aluminum, anodized aluminum, magnesium, silver, gold, platinum,palladium, iridium, alloys thereof, and coated metals.

Suitable polymers include, but are not limited to, hydrophilic polymers,polar polymers, hydrophilic copolymers, polar copolymers, hydrophobicpolymers/copolymers, non-polar polymers/copolymers, and combinationsthereof, such as polysaccharides, polypeptides, polyacrylic acid,polyhydroxybutyrate, polymethacrylic acid, functionalized polystyrene(including but not limited to, sulfonated polystyrene and aminatedpolystyrene), nylon, polybenzimidazole, polyvinylidenedinitrile,polyvinylidene chloride and fluoride, polyphenylene sulfide,polyphenylene sulfone, polyethersulfone, polymelamine, polyvinylchloride, polyvinylacetate, polyvinylalcohol, co-polyethylene-acrylicacid, polyethylene terephthalate, ethylene-vinyl alcohol copolymers,polyethylene, polychloroethylene, polypropylene, polybutadiene,polystyrene, polyphenol-formaldehyde, polyurea-formaldhyde, polynovolac,polycarbonate, polynorbornene, polyfluoroethylene,polyfluorochloroethylene, polyepoxy, polyepoxyvinylester,polyepoxynovolacvinylester, polyimide, polycyanurates, silicone, liquidcrystal polymers, derivatives, composites, nanoparticle reinforced, andthe like.

In some cases, fibers can be treated for wetting with preferred phases,to protect from corrosion by the process streams, and/or coated with afunctional polymer. For instance, carbon fibers can be oxidized toimprove wettability in aqueous streams and polymer fibers can displayimproved wettability in aqueous streams and/or be protected fromcorrosion by incorporation of sufficient functionality into the polymer,including but not limited to, hydroxyl, amino, acid, base, enzyme, orether functionalities. In some cases, the fibers may include a chemicalbound (i.e., immobilized) thereon to offer such functionalities. In someembodiments, the fibers may be ion exchange resins, including thosesuitable for hydroxyl, amino, acid, base or ether functionalities. Inother cases, glass and other fibers can be coated with acid, base, orionic liquid functional polymer. As an example, carbon or cotton fiberscoated with an acid resistant polymer may be applicable for processingstrong acid solutions. In some cases, fibers may include materials thatare catalytic or extractive for particular processes. In some cases, theenzymatic catalysts may comprise the fibers to aid in particularreactions and/or extractions.

In some embodiments, all the fibers within a conduit reactor may be ofthe same material (i.e., have same core material and, if applicable, thesame coating). In other cases, the fibers within a conduit reactor mayinclude different types of materials. For example, a conduit reactor mayinclude a set of polar fibers and a set of non-polar fibers. Other setsof varying materials for fibers may be considered. As noted above, theconfiguration of fibers (e.g., shape, size, number of filamentscomprising a fiber, symmetry, asymmetry, etc.) within a conduit reactormay be the same or different for the processes described herein. Suchvariability in configuration may be in addition or alternative to avariation of materials among the fibers. In some embodiments, differenttypes of fibers (i.e., fibers of different configurations and/ormaterials) may run side by side within a reactor with each set havingtheir own respective inlet and/or outlet. In other cases, the differenttypes of fibers may extend between the same inlet and outlet. In eitherembodiment the different types of fibers may be individually dispersedin the conduit reactor/contactor or, alternatively, each of thedifferent fiber types may be arranged together. In any case, the use ofdifferent types of fibers may facilitate multiple separations,extractions, and/or reactions to be performed simultaneously in aconduit reactor from a singular or even a plural of continuous phasestreams. For example, in a case in which a conduit reactor/contactor isfilled with multiple bundles of respectively different fiber types eachconnected to its own constrained phase fluid inlet and arrangedoff-angle, the bundles could be arranged for the continuous phase fluidto pass sequentially over the multiple fiber bundles with differentmaterials extracted by or from each bundle.

The constrained phase of a process conducted in a fiber conduit reactorcan include any liquid that wets the fibers preferentially to thecontinuous phase, including but not limited to, such materials asorganophosphorus acids, water, water solutions, water and co-solvents,alcohols, phenols, amines (including but not limited to, polyamines,ethanolamines, and polyethanolamines), carboxylic acids, ethers, esters,dimethyl sulfoxide, sulfone, dimethyl formamide, ketones, aldehydes,saturated and unsaturated aliphatic hydrocarbons, aromatic hydrocarbons,silicone containing fluids, halogenated solvents, liquefied gases,sulfuric acid, other mineral acids, liquid metals/alloys, and ionicliquids. The scope of the ionic liquids which may be utilized in themethods described herein is set forth in detail below. The continuousphase of a process conducted in a fiber conduit reactor can include anyliquid immiscible with the selected constrained phase. Immiscible ionicliquids for example can be used together, one as a constrained phase andone as a continuous phase.

For extraction processes, the constrained phase frequently comprises theextractant, but functionalities of the constrained phase and thecontinuous phase can be reversed if desired by reversing the polarity ofthe fibers chosen for a particular separation. In some cases, a solventmay be the extractant. In other embodiments, an extractant may be mixedwith a solvent (i.e., the solvent may be used as a carrier medium forthe extractant). In either case, extractant is frequently diluted inanother solvent. Examples of diluted extractants which may be used forsome processes include but are not limited to Ionquest-801 (anorganophosphorus acid) diluted in an aliphatic organic compound;1-phenyl-3-methyl-4-benzoly-5-pyrazolone (HPMBP) as the extractant inaqueous-chloroform; D2EHPA, acetylacetone and 1,10-phenanthroline innon-polar organic solvents. In some embodiments, the phase used forextraction may include two immiscible liquids to affect selectiveextraction for multiple entities. For instance, a continuous phase oftwo immiscible liquids may be used to extract different metals from afluid stream in the constrained phase or vice versa. Such a process maybe advantageous to avoid having to process (i.e., wash) an extractantsolution discharged from a fiber conduit reactor. In some cases, twoimmiscible ionic liquids may be used to affect selective extraction ofentities, such as different metals.

The term ionic liquid (IL) is used herein to refer to a salt in a liquidstate. In some cases, the term is specific to salts having a meltingpoint below 100° C. ILs are also known as liquid electrolytes, ionicmelts, ionic fluids, or liquid salts. An advantage of ILs is their highsolvation ability for compounds of widely varying polarity. Furthermore,utilizing ILs is one of the goals of green chemistry because ILspotentially create a cleaner and more sustainable chemistry asenvironmental friendly solvents for many extractive, reactive, andcatalytic processes. Moreover, utilizing ILs offer potential improvementin process economics, chemical reactivity, selectivity, and yield. Assuch, it may be particularly advantageous, in some cases, to employionic liquids for the processes described herein.

A specific category of ionic liquids are room temperature ionic liquids(RTILs), which are salts having a melting point at or below roomtemperature (i.e., at or below 20° C.). RTILs have advantages overconventional organic diluents, such as negligible vapor pressure, lowflammability, moisture stability, relatively high radiation stability,different extraction properties and a possibility of eliminating aqueousphase acidification. Furthermore, it has been demonstrated thatextraction efficiency of RTIL can be modulated by a chelating agent. Forexample: 1) highly efficient extraction of strontium ions can beachieved when dicyclohexane-18-crown-6 (DC18C6) is combined with RTILs;2) the extraction of various alkali metal ions can be achieved withcrown ethers in RTILs; 3)octyl(phenyl)-N,N-diisobutylcarbamoylmethyl-phosphine oxide dissolved inRTILs enhanced the extractability of lanthanides and actinides incomparison to conventional organic solvents; 4) the extraction of silverions is greatly enhanced by a combined application of RTIL andcalyx[4]arene compared to that of chloroform; 5) task-specific RTILswith coordination capacity built in the RTIL cation have been reported;and 6) increased efficiency has been shown of chelate extraction of3d-cations like Cs with 8-sulfonamidoquinoline, Pu(IV) withcarbamoylmethylphosphine oxide, and uranyl ion with tributylphosphate.As such, it may be particularly advantageous, in some cases, to employRTILs for the processes described herein. As an example, theaforementioned embodiments of metal extraction using RTILs may beperformed in a fiber conduit reactor.

ILs are usually formed by a large organic cation combined with an anionof smaller size and more symmetrical shape, although some symmetriccations are also combined with asymmetric anions to form ionic liquids.In spite of their strong charges, their asymmetry prevents them fromsolidifying at low temperatures. Furthermore, ionic liquids can be madehydrophilic or hydrophobic. Some common cations which may be consideredfor the formation of ILs employed herein are imidazolium,benzotriazolium, pyrrolidinium, piperidinium, pyridinium,isoquinolinium, thiazolium, sulfonium, ammonium, phosphonium andaminium, but other cations may be considered. Some common anions whichmay be considered for the formation of ILs employed herein are halide,borate, carbon icosahedral, nitrite, amides, imides, nitrate,hydrofluoride anions, aluminate, mesylate, sulfate, sulfinates,sulfonates, tosylate, sulfate, phosphate, acetate, alkanoates,aluminate, arsenic, niobium, tantalum and trisubstitued methane, butother anions may be considered. In particular, a comprehensive databasefrom literature date between 1980 and 2004 has been published denoting276 kinds of cations and 55 kinds of anions suitable for IL formation(“Physical Properties of Ionic Liquids: Database and Evaluation,” J.Phys. Chem. Ref. Data, Vol. 35, No. 4, 2006).

ILs are advantageous because they can be tuned with a well-judgedselection of the cation-anion pair, giving the opportunity to chooseamong a vast range of different ionic liquids. In particular, hundredsof ionic liquids have been synthesized and there is virtually no limitin the number of possible counter-ion pairs and mixtures of them thatcan be obtained. In fact, the number of possible ionic liquids isestimated around 10¹⁸, whereas the number of traditional solvents widelyused in industry is only a few hundred. ILs based on a specific organiccation and/or anion for several potential specific applications areknown, examples of which include chiral ionic liquids (using natural orsynthesized chiral units) for asymmetric catalytic transformations,enantioselective resolution or separation processes; pharmaceuticalionic liquids (called API-ILs incorporating an active principleingredient as cation or anion); magnetic ionic liquids (based on FeCl4anions) for efficient separation processes; and as intrinsicallyfunctional materials (for example luminescent, photochemical orelectrochemical ILs).

In addition, IL compounds can also be tuned by the modification of thecation and/or the anion molecular structure adding appropriatefunctional groups in order to obtain ionic liquids with a set of desiredphysico-chemical properties, which are known as task specific ionicliquids (TSIL). In particular, supramolecular structure and organizationhave emerged as important and complicated topics that may be key tounderstanding how chemical reactions and other processes are affected byionic liquids. In general, TSILs may be developed with desiredphysico-chemical properties such as density, thermal/electricalconductivity, viscosity, polarity, and non-toxic or biodegradable ILs.For example, protic ILs generally have stronger polarities and candissolve metal salts to a greater extent than common aprotic ILs. Theseprotic ILs have been utilized in the electrodeposition of silver andzinc. As another example, N-alkylethylenediamines have two amines andare more favorable for an incorporation of Lewis acids such as protonand transition metal ions into the ILs in comparison with N-alkylamines.

In addition to the above parameters for varying properties, it has alsobeen reported that replacing one atomic element in an ionic species withanother heavier element affects the physical and chemical properties ofILs in unexpected ways. For instance, comparison of ILs with C and Si ina side group of 1-methyl-3-neopentylimidazolium and1-methyl-3-trimethylsilyl-methyl-imidazolium with the same anion showedthat shear viscosities of the silicon substituted ILs were substantiallyless than those of the respective carbon ILs. Heavy atom substitutionalso affects the static properties such as liquid density, shearviscosity, and surface tension. This feature of ILs is the opposite ofthat observed in conventional neutral molecular liquids.

Computer modeling tools are being developed that will enable ILs to bedesigned for specific tasks. Two different and complementary approacheshave shown excellent predictive power: (1) the soft-SAFT equation ofstate, used to predict the solubility of several compounds in differentfamilies of alkylimidazolium ionic liquids, as well as interfacialproperties, and (2) classical molecular dynamic simulations, used tostudy transport properties like self-diffusion, viscosity and electricalconductivity of ionic liquids. These tools help in getting additionalinsights into the underlying mechanisms governing the behavior of thesesystems, which is the basic knowledge needed for a rational design ofTSILs. It is noted that TSILs may be advantageous for any of theapplications disclosed herein.

Turning to FIG. 1, which depicts a fiber conduit reactor similar to theone disclosed in U.S. Pat. No. 3,977,829, conduit 10 has a bundle ofelongated fibers 12 filling conduit 10 for a portion of its length.Fibers 12 are secured to tube 14 at node 15. Tube 14 extends beyond oneend of conduit 10 and has operatively associated with its metering pump18 which pumps a first (constrained) phase liquid through tube 14 andonto fibers 12. Operatively connected to conduit 10 upstream of node 15is inlet pipe 20 having operatively associated with it metering pump 22.This pump 22 supplies a second (continuous) phase liquid through inletpipe 20 and into conduit 10, where it is squeezed between theconstrained coated fibers 12. At the downstream end of conduit 10 isgravity separator or settling tank 24 into which the downstream end offibers 12 may extend. Operatively associated with an upper portion ofgravity separator 24 is outlet line 26 for outlet of one of the liquids,and operatively associated with a lower portion of gravity separator 24is outlet line 28 for outlet of the other liquid, with the level ofinterface 30 existing between the two liquids being controlled by valve32, operatively associated with outlet line 28 and adapted to act inresponse to a liquid level controller indicated generally by numeral 34.

Although the fiber conduit contactor shown in FIG. 1 is arranged suchthat fluid flow traverses in a horizontal manner, the arrangement of thefiber conduit contactor is not so limited. In particular, in some cases,the fiber conduit contactor may be arranged such that inlet pipes 14 and20 as well as node 15 occupies an upper portion of the apparatus andsettling tank 24 occupies the bottom portion of the apparatus. Forexample, the fiber conduit contactor shown in FIG. 1 may be rotatedapproximately 90° in parallel with the plane of the paper to arrangeinlet pipes 14 and 20, node 15 and settling tank 24 in the noted upperand lower positions. Such an arrangement may capitalize on gravityforces to aid in propelling fluid through the reactor. In yet otherembodiments, the fiber conduit contactor depicted in FIG. 1 may berotated approximately 90° in the opposite direction parallel with theplane of the paper such that inlet pipes 14 and 20 and node 15 occupiesthe bottom portion of the apparatus and settling tank 24 occupies theupper portion of the apparatus. In such cases, it was discovered thatthe hydrophilicity, surface tension, and repulsion of the continuousphase fluid will keep the constrained phase fluid constrained to thefibers regardless of whether the fluids are flowing up, down, orsideways and, thus, sufficient contact can be attained to effect thedesired reaction and/or extraction without the need to counter gravityforces. It is noted that such an inverted arrangement of a fiber conduitcontactor is applicable for any of the extraction processes describedherein as well as any other type of fluid contact process that may beperformed in a fiber conduit contactor/reactor. It is further noted thatfiber conduit contactors may be arranged in a slanted position for anyof the extraction processes described herein or for any other processthat may be performed in a fiber conduit contactor/reactor (i.e., thesidewalls of the fiber conduit contactor may be arranged at any anglebetween 0° and 90° relative to a floor of a room in which the fiberconduit contactor is arranged).

In an alternative embodiment, a counter-current fiber conduitcontactor/reactor may be used for the methods described herein. Anexample of a counter-current fiber conduit contactor/reactor isillustrated in FIG. 2. In particular, FIG. 2 illustrates an alternativeconfiguration of the fiber conduit contactor/reactor depicted in FIG. 1,specifically that the locations of inlet pipe 20 and associated pump 22have been switched with outlet line 26 to affect counter-current flow ofthe continuous phase relative to the flow of the constrained phase inconduit 10. Similar to the fiber conduit contactor/reactor depicted inFIG. 1, the fiber conduit contactor/reactor depicted in FIG. 2 includesconduit 10 having a bundle of elongated fibers 12 secured to tube 14 atnode 15 and extending a portion of the length of conduit 10. Tube 14extends beyond one end of conduit 10 and has operatively associated withits metering pump 18 which pumps a first (constrained) phase liquidthrough tube 14 and onto fibers 12. At the other end of conduit 10 issettling tank 24 into which fibers 12 extend and unload the first phaseliquid. Outlet line 28 is arranged at a lower portion of settling tank24 for discharge of the first phase liquid as controlled by valve 32,which operates in response to level monitor 34 arranged at interface 30.

As noted above, the fiber conduit contactor/reactor/receiver depicted inFIG. 2 differs from the one depicted in FIG. 1 by the locations of inletpipe 20 and associated pump 22 have been switched with outlet line 26.In particular, inlet pipe 20 and associated pump 22 in FIG. 2 areconnected to an upper portion of settling tank 24 to introduce a second(continuous) phase liquid into settling tank 24 and conduit 10, where itis squeezed between the fibers 12 coated with the first constrainedphase liquid. In addition, the fiber conduit contactor/reactor depictedin FIG. 2 includes outlet 26 for the discharge of the second continuousphase liquid from conduit 10 into collection tank 29. An optionaladdendum to the fiber conduit contactor configuration depicted in FIG. 2would be to add an extension line from pipe 20 to conduit 10 near itsport to settling tank 24. Such an additional extension line may be usedto feed the second (continuous) phase liquid into conduit 10 whilebypassing settling tank 24. In any case, due to the configuration of thecontactor/reactor/receiver depicted in FIG. 2, the size of its settlingtank 24 may be optionally reduced by up to 50% relative to the size usedfor the fiber conduit contactor/reactor/receiver depicted in FIG. 1

In any case, with the counter-current fiber conduit contactorconfiguration depicted in FIG. 2, it was discovered that thehydrophilicity, surface tension, and repulsion of the continuous liquidphase will keep the constrained phase liquid constrained to the fiberseven when the constrained phase liquid is flowing in the oppositedirection. Such a phenomenon is true in cases in which the constrainedphase liquid is flowing up, down, or sideways and, thus, although thecounter-current fiber conduit contactor shown in FIG. 2 is arranged suchthat fluid flow traverses in a horizontal manner, the arrangement of thefiber conduit contactor is not so limited. In particular, thecounter-current fiber conduit contactor shown in FIG. 2 may be rotatedapproximately 90° in either direction parallel with the plane of thepaper to respectively arrange inlet pipe 14 and settling tank 24 inupper and lower positions of the apparatus or vice versa. In yet otherembodiments, the fiber conduit contactor depicted in FIG. 2 may bearranged in a slanted position (i.e., the sidewalls of the fiber conduitcontactor may be arranged at any angle between 0° and 90° relative to afloor of a room in which the fiber conduit contactor is arranged). Inany case, the counter-current fiber conduit contactor depicted in FIG. 2may be used for any of the extraction processes described herein or forany other process that may be performed in a fiber conduitcontactor/reactor.

Turning back to FIG. 1, during operation of an apparatus such as thatdepicted in FIG. 1, an extractant liquid, such as an IL, is introducedthrough tube 14 and onto fibers 12. Another liquid, such as a leachatecontaining dissolved metal ions, is introduced into conduit 10 throughinlet pipe 20 and through void spaces between fibers 12. Fibers 12 willbe wetted by the extractant preferentially to the other liquid. Theextractant will form a film on fibers 12, wherein the film will bedragged downstream through conduit 10 by the passage of the other liquidtherethrough. As a consequence of the relative movement of the otherliquid with respect to the extractant film on fibers 12, a newinterfacial boundary between the other liquid phase and the extractantis continuously being formed, and as a result, fresh liquid is broughtin contact with the extractant, thus causing and accelerating theextraction. One skilled in the relevant art would understand theapplicability of various extractant compositions and reaction conditionsto achieve the desired result. For example, a phase transfer catalyst orco-solvent can be optionally employed to facilitate mass transfer acrossthe interface between the phases. The phase transfer catalyst and/orco-solvent may be introduced to the conduit reactor in the constrainedphase, the continuous phase, or both phases. Useful phase transfercatalysts for reactions include, but are not limited to, quaternaryammonium compounds, quaternary phosphonium compounds, sulfoniumcompounds, crown ethers, polyglycols, and combinations thereof.

Regardless of the type of liquids used for the constrained andcontinuous phases, both phases will be discharged into separator 24. Insome cases, the volume of the liquid which is not the extractant will begreater in the separator because the extractant may move at a slowervelocity than the other liquid phase. In some embodiments, theextractant will collect in the lower portion as it may be heavier(denser) than the other liquid. In other cases, the extractant may beless dense than the other liquid. In either case, because theconstrained phase follows the fibers and the liquid phases come out ofthe conduit reactor separated, the process described herein may beutilized even when the phases are very close in density. Although theembodiment shown in FIG. 1 describes an arrangement wherein thedownstream end of fibers 12 extends into separator 24 below interface 30so that the heavier liquid can be collected directly in the bottom ofseparator 24 without it being dispersed into the other liquid, thearrangement of fibers 12 is not so limited. In particular, in someembodiments, the downstream end of fibers 12 within separator 24 may bealternatively disposed above or at the interface between the liquidphases within separator 24, depending on the relative density of theconstrained phase and the continuous phase. Although the aforementionedexample description of FIG. 1 mentions the use of an IL solution as theconstrained phase and leachate as the free phase, use of these types ofliquids is only an example. Any suitable materials comprisingsubstantially immiscible phases may be employed to effect an extractionor reaction.

FIG. 3 shows a conduit reactor system useful for the processes describedherein. In operation, the secured fibers in Reactors 1 and 2 are wettedby the constrained phase (denoted in FIG. 3 as “IL in”) before themobile phase (denoted in FIG. 3 as “Leachate in”) is started. FIG. 3shows how multiple fiber reactors can be used to increase efficiency ofutilization of reactants and to increase extraction of species byessentially feeding the liquids counter-currently through the reactorsequence. The continuous phase output of Reactor 1 (denoted in FIG. 3 as“Leachate Out”) is introduced to Reactor 2 (denoted in FIG. 3 as“Leachate In”) and further processed thereby. The constrained phaseoutput of Reactor 2 is introduced to Reactor 1 (“IL In”) while theconstrained phase output of Reactor 1 is processed to remove theconcentrated metals (or alternatively introduced to another reactorupstream of Reactor 1 (not shown). In FIG. 3, the constrained and mobilephases are depicted as flowing co-currently through each individualreactor, but the constrained and continuous phases may flowcounter-currently through the reactor sequence. In some cases, a freshIL or a different IL can be used with each reactor if desired. Althoughthe description of FIG. 3 discusses the use of an IL solution as theconstrained phase and leachate as the free phase, use of these types ofliquid is only an example. Any suitable materials comprisingsubstantially immiscible phases may be employed to effect an extractionor reaction.

FIG. 4 shows a conventional shell and tube heat exchanger. Combiningthis design with a fiber conduit reactor yields a fiber conduit reactordesign (not shown) adapted to handle reactions/extractions that need tobe cooled or heated. One can see that modification of the inlet of theheat exchanger tubes (“Tube Inlet”) to duplicate the inlets shown inFIG. 1 would make each tube in the exchanger act like a thermallycontrolled fiber reactor (not shown). The exit end of the heat exchanger(“Tube Outlet”) can be modified to operate as a separator (not shown) tocollect the extract phase, such an as IL, on the bottom near the end ofthe fibers (not shown) and allow the other liquid phase, such as aleachate, to exit from the top of the separator section. Introduction ofa heat exchange medium to the exchanger (via “Shell Inlet”) and outflowthereof (via “Shell Outlet”) allows for the addition or removal ofthermal energy from the exchanger tubes. While FIG. 4 depicts acounter-current flow heat exchanger, a co-current arrangement could alsobe used in conjunction with the process described herein. In addition,although baffles are shown on the shell side of the exchanger in FIG. 4,the process described herein is not so limited and a heat exchangerwithout baffles may be employed.

Example 1

This example illustrates the use of a fiber conduit reactor comprising a12″×½″ stainless steel tube containing approximately 550,000 glassfibers 14 inches in length to primarily recover rhenium from wastesuperalloy. The liquid volume of the reactor was approximately 18 mL.Superalloy powder was dissolved in oxidizing acid. Two different solventextraction experiments were performed by contacting a stream ofapproximately 1 ml/min of acid solution of superalloy on the fiberswith 1) approximately 1 mL/min of kerosene containing extractantstrioctyl amine and tributyl phosphate and 2) approximately 1 mL/min ofkerosene containing tributyl amine and aliquat 336. Both experimentswere performed at room temperature (i.e., between 20-30° C.). Pressurein the reactor during both experiments was less than 1 psig, indicatinglittle to no accumulation of crud. The phases emerged from the reactorseparated and flowed into the receiver. The lower aqueous phase wasanalyzed for the concentrations of metal ions. Table 1 shows that 91% ofthe rhenium was extracted in one step when extractants trioctyl amineand tributyl phosphate were used. In the same run, rhenium wasselectively extracted compared to tantalum and nickel, which were onlyabout 16% extracted.

TABLE 1 Extraction of Rhenium, Tantalum and Nickel from DissolvedSuperalloy Distribution Separation M in, mg/L M out, mg/L % extractionCoefficients Factors Re Ta Ni Re Ta Ni Re Ta Ni DRe DTa DNi S_(Re,Ta)S_(Re,Ni) 1 602 13 17116 57 11 14151 91 16 17 9.6 0.2 0.2 49 46 2 397962 222 626 44 35 1 20% Trioctyl Amine/30% Tributyl Phosphate inKerosene 2 Tributyl Amine and Aliquat 336 in Kerosene

Example 2

This example illustrates the use of a fiber conduit reactor comprising a12″×½″ stainless steel tube containing approximately 550,000 glassfibers 14 inches in length to extract and separate rare earth elementsfrom a simulant pregnant leach solution. The liquid volume of thereactor was approximately 18 mL. The simulant pregnant leach solution(PLS) was prepared by dissolving Y and Yb in acid solution. A firstexperiment was performed by contacting a stream of approximately 1ml/min of acid PLS solution on the fibers with approximately 1 mL/min ofkerosene containing a commercial extractant of bis (2-ethyl hexyl)phosphate. A second experiment was performed with the same solutions,but at approximately twice the flow rate. Both experiments wereperformed at room temperature (i.e., between 20-30° C.). Pressure in thereactor during both experiments was less than 1 psig, indicating littleto no accumulation of crud. The phases emerged from the reactorseparated and flowed into the receiver. The upper aqueous phase wasanalyzed for the concentrations of metal ions. Table 2 shows the firstexperiment run at flow rates of approximately 1 mL/min for the aqueousacidic simulated PLS and the commercial extractant bis (2-ethyl hexyl)phosphate in kerosene gave excellent extraction efficiencies of 97% of Yand 99% of Yb in one stage. The same solutions run at approximatelytwice the flow rate yield extraction efficiencies of 81% of Y and 97% ofYb in one stage.

Example 3

Addition extraction experiments were conducted utilizing the PLSsolution described in Example 2 in the same reactor described in Example2 with an experimental extractant developed for solvent extraction ofREE. The experimental extract was labeled as “Cyanex 572”, but the trueidentity was not provided. As show in the last two lines of Table 2,excellent results for selective extraction of Yb versus Y were achieved.A 28 minute process time through the fiber conduit reactor gave aseparation factor Yb:Y of 206 and a shorter process time, specifically14 minutes of process time through the fiber conduit reactor, yielded ahigher separation factor Yb:Y of 2123.

TABLE 2 Extraction and Separation of Y and Yb Surrogate solutionSurrogate after solution, extraction % (mg/L) (mg/L) extractionExtraction Y Yb Y Yb Y Yb D_(Y) D_(Yb) S_(Yb,Y) Time (min) 5252 2704144.6 22.74 97.3 99.2 35.3 118 3.3 28 5252 2704 1021 70 80.6 97.4 7.5 689.1 14 5252 2704 5195 830 1.1 69.3 0.01 2.3 206 25 5252 2704 5251 20430.02 24.4 0.0002 0.3 2123 15 Lines 1 and 2: Simulated PLS andextractant-bis (2-ethyl hexyl) phosphate in kerosene processed at flowrates of approximately 1 mL/min and 2 mL/min, respectively Lines 3 and4: >99% Separation of Yb versus Y from simulated PLS utilizing anexperimental extractant at flow rates of approximately 1 mL/min and 2mL/min, respectively

Example 4: ILs and Organic Solvents in a TALSPEAK Process

This example is modeled from a published batch process experiment whichutilized the same process solutions for the noted extraction. The noteddata is the same as the published batch process experiment on thepresumption that similar if not better results will be achieved using afiber conduit reactor. In this simulation, a fiber conduit reactorcomprising a 36″×½″ stainless steel tube containing approximately550,000 glass fibers 42 inches in length is contemplated for use. Theliquid volume of this reactor is approximately 35 mL. Simulatedextraction experiments involve contacting a stream of 0.5 ml/min ofbutyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide (see,component 1) containing 40 mM of HDEHP (see, Component 2) with a streamof 5 ml/min of lanthanide-containing aqueous solution in the fiberconduit reactor. The phases emerge from the reactor separated. The upperaqueous phase is analyzed for the concentrations of lanthanide ions. Theprocedure is repeated with diisopropylbenze (DIPB) as the solvent. Table3 shows simulated distribution coefficients (Dm) using the ½″×36″ fiberreactor for lanthanide extraction from aqueous solutions. A distributioncoefficient greater than 1 represents an overall preference for the ILphase. In other words, the larger the distribution coefficient, thegreater amount of extraction for the noted element.

TABLE 3 Ionic Liquids and Organic Solvents in a TALSPEAK Fiber ProcessDistribution Coefficient Solvent:Leachate, Dm La Nd Eu Er Yb Lu IonicLiquid Solvent 700 375 75 775 1175 1510 DIPB Solvent 0 0 0 5 60 75

Example 5: Extraction of Butanol from Fermentation Broth

Biobutanol has received major attention as an alternative fuel andadditive to fossil fuels. Biobutanol produced via fermentation ishampered by low butanol concentrations (<1.5%) in the fermentationbroth. An efficient separation process is required if biobutanolproduction is to be economically viable. In this example, liquid-liquidextraction of butanol from water, employing a designed task-specificionic liquid (TSIL), tetraoctylammoniumnapthenate (TOAMNaph) issimulated and is compared to a simulated process utilizing oleyl alcohol(OA). These experiments are modeled from published batch processexperiments which utilized the same process solutions for the notedextraction. The noted data is the same as the published batch processexperiments on the presumption that similar if not better results willbe achieved using a fiber conduit reactor. For this simulation,parameters for extraction of 1% butanol in water with the two solventsare given in Table 4. Simulating use of the same fiber conduit reactoras Example 1, a solution of 1% butanol in water is pumped through thereactor at 5 mL/min along with 0.4 mL/min of TOAMNaph at 25° C. Thesimulated results are given in Table 5. Likewise, a solution of 1%butanol in water is pumped through the reactor at 5 mL/min along with3.4 mL/min of OA at 25° C. The simulated results are given in Table 5.Note that both OA and TOAMNaph are effective extractants, but the taskspecific ionic liquid is much more efficient.

TABLE 4 Extraction Parameters for Solvent Extraction of 1% Butanol OA[TOAMNaph] Selectivity 194 274 Distribution 3.4 21 Coefficient

TABLE 5 Extraction Results for Solvent Extraction of 1% Butanol Wt. %Butanol in Wt. % Feed Butanol Water in Solvent Feed 100 0 OA 29 71TOAMNaph 5 95

Example 6: Ionic Liquids and Organic Solvents in Effluent ExtractionFiber Process

Distillery effluents are often contaminated streams with chemical oxygendemand (COD) values of up to 48,000 mg/l and low pH values of between 3and 4. Effluent from a wine distillery consists primarily of organicacids with a high soluble biodegradable COD fraction of up to 98%. Table6 denotes a typical composition of a wine distillery waste stream withrespect to organic acids. This effluent stream must be treated to reducethe COD concentration to acceptable levels for discharge to a municipalsewer.

TABLE 6 Typical organic acid composition of wine distillery effluentTartaric acid 27% Malic acid 8% Lactic acid 29% Succinic acid 26% Aceticacid 10%

The following experiment is modeled from a published batch processexperiment which utilized the same process solutions for the notedextraction. The noted data is the same as the published batch processexperiment on the presumption that similar if not better results will beachieved using a fiber conduit reactor. Simulating the use of the samefiber conduit reactor as described in Example 1, lactic acid solutionsin water and three different trials of n-dodecane containing varyingconcentrations of ionic liquid extractant Cyphos IL-104 are pumped intothe reactor at 5 mL/min at 25° C. The experiment was simulated withtrialkylamine as the extractant in n-dodecane. The distributioncoefficient (D) for each run is determined. The results are given inTable 7 and shows Cyphos IL-104 is an efficient extractant for thisapplication.

TABLE 7 Ionic Liquids and Organic Solvents in Lactic Acid ExtractionFiber Process Cyphos IL-104 A B C Trialkylamine Lactic acid in water,kmol/m3 1.1 1.1 1.1 1.1 IL in dodecane, kmol/m3 0.72 0.3 0.018 Amine indodecane, kmol/m3 0.42 D 1.8 5 10.7 1 IL = Cyphos IL-104,trihexyl-tetradecyl)phosphonium bis 2,4,4-trimethylpentylphosphinate

Example 7: Extraction of Dye from Aqueous Stream

Azo dyes are commonly used in the leather and textile industries.However, they are not totally consumed in the process and they arefrequently not recovered from process water. The leather industrytypically discharges 10-15% of the dye in the plant effluent. Thiscreates both environmental and economic issues. There is a need toremove residual dye from the large volume of aqueous effluent. Inleather processing, dye-containing effluents can be treated byabsorption using charcoals, activated carbons, clays, soils,diatomaceous earth, etc. The disadvantage of adsorption processes isthat the adsorbent needs to be regenerated, which adds to the cost ofthe process, and is sometimes very time-consuming. Chemical treatmentsfor decolorization of wastewater include reduction, oxidation,complexation, ion exchange, and neutralization. Oxidation is the mostcommonly used chemical decolorization process. Enzymaticreduction/oxidation reactions can decolorize, but the products of azodye degradation are mostly aryl amines which are more carcinogenic andtoxic than the original effluents. The drawback with all of thesemethods is the duration of the treatment, which normally ranges from 1to 6 days. Thus, these methods do not provide an acceptable long termsolution.

In this example, azo dyes were extracted from water into a neutral ionicliquid demonstrating feasibility to minimize pollution of waste-watersand decrease dye costs. This experiment is modeled from a publishedbatch process experiment which utilized the same process solutions forthe noted extraction. The noted data is the same as the published batchprocess experiment on the presumption that similar if not better resultswill be achieved using a fiber conduit reactor. Simulating the use ofthe fiber conduit reactor described in Example 1, an aqueous streamcontaining red dye is pumped through the reactor at 5 mL/min with anionic liquid stream at 2.5 mL/min. This is repeated two more times togive 96% removal of the dye as shown in Table 8.

TABLE 8 Extraction of red dyes from an effluent sample into an ionicliquid Number Residual Abs Extraction conc. Dye (nm) Stages (×10⁻⁴ g/L)Red 523 0 1.43 1 0.85 3 0.05

Example 8: Enantioselective Extraction of Optically Active Drug Isomers

There is a growing demand for optically pure compounds in the chemicalindustries, because the left- and right-handed enantiomers of chiral,bioactive compounds often exhibit different physiological effects onpharmacological activity, the metabolism process, and toxicity wheningested by living organisms. For example, ibuprofen(2-(4-isobutylphenyl)propionic acid (IBU) is used as a nonsteroidalanti-inflammatory drug, which is still sold as a racemic mixture. S-IBU,however, is 28 times more physiologically active than the R-IBU whichcan cause gastrointestinal toxicity, water retention, and other sideeffects. Enantioselective chemical production can be achieved byenantioselective methods to separate racemic mixtures. The most commontechnique for obtaining enantiopure compounds is the separation ofenantiomers. Various separation methods including crystallization andchromatography have been developed. Existing methods, however, are notalways applicable for most racemic mixtures. Chiral solvent extractionis a potentially attractive technique which is cheaper and easier toscale up to commercial scale and has a large application range. Aneconomically feasible reactive extraction system requires not only highenantioselectivity but also sufficiently fast kinetics. A properlychosen extractant can provide enantioselectivity and a fiber conduitreactor can provide the surface area for fast processing using one ormore stages.

The following experiment is modeled from a published batch processexperiment which utilized the same process solutions for the notedextraction. The noted data is the same as the published batch processexperiment on the presumption that similar if not better results will beachieved using a fiber conduit reactor. Simulating the use of the samefiber conduit reactor as described in Example 1, a solution of 0.1 mol/Lof hydroxypropyl-β-cyclodextrin (HP-β-CD) dissolved in an aqueousNH2PO4/H3PO4 buffer solution (pH 2.5) and 1 mmol/L racemic IBU dissolvedin cyclohexane are both pumped through the reactor at 5 mL/min at 10° C.The distribution coefficients of IBU enantiomers are determined and aregiven in Table 9. As shown, cyclohexane/(HP-β-CD) is an enantioselectiveextractant for racemic IBU.

TABLE 9 Enantioselective Separation of Racemic IBU DistributionDistribution Coefficient, Coefficient, P_(R) P_(S) Enantioselectivity, α3.09 3.79 1.23

Example 9: Extraction of Sulfur Compounds from Diesel

Hydrodesulfurization (HDS) is used for the removal of sulfur compoundsin the petroleum refining industry. HDS eliminates aliphatic andnon-aliphatic sulfur compounds effectively. But benzothiophene anddibenzothiophene (DBT), type compounds are difficult to remove by HDS.An advantage of some extraction processes is that they can be carriedout at normal temperature and pressure. Protic ionic liquids (PILs) haveexcellent physical and chemical properties as those of traditional ILsbut also have unique advantages, such as high extraction efficiency, lowcost, low viscosity, easy recycling, and environmental friendly. In thisexample, the removal of DBT from oil by amine-based PILdimethylaminopropionitrile propionate [DMAPN][CO2Et] is illustrated.This experiment is modeled from a published batch process experimentwhich utilized the same process solutions for the noted extraction. Thenoted data is the same as the published batch process experiment on thepresumption that similar if not better results will be achieved using afiber conduit reactor. Simulating the use of the same reactor asdescribed in Example 1, a 1% DBT solution in n-octane and PIL extractant[DMAPN][CO2Et] are both pumped through the reactor at 5 mL/min at 25° C.The concentration of DBT in the oil was determined for the feed as wellas four successions of treating the oil. The results are given in Table10. As shown, [DMAPN][CO2Et] is an efficient extractant for thisapplication.

TABLE 10 Desulfurization of Oil by PIL [DMAPN][CO2Et] Residual S Numberof Concentration Extraction Stages (ppm) Feed 1600 1 650 4 50

Example 10: Extraction of Diacetin, Monoacetin, and/or Glycerol fromBiodiesel-Triacetin Mixtures

The following experiment is modeled from a published batch processexperiment which utilized the same process solutions for the notedextraction with centrifugation between each stage. The noted data is thesame as the published batch process experiment on the presumption thatsimilar if not better results will be achieved using a fiber conduitcontactor. Simulating the use of the same fiber conduit contactor asdescribed in Example 1, a mixture of biodiesel, triacetin, diacetin,monoacetin and glycerol was introduced into the fiber conduit contactoras the constrained phase at a rate of 5 mL/min. In addition, 0.25 mL/minof deionized water was introduced into the fiber conduit contactor asthe continuous phase, yielding an aqueous phase to organic phase ratioof 0.05. The organic mixture was processed through the fiber conduitcontactor two more times at the same 0.05 aqueous phase to organic phaseratio. The final organic phase (raffinate) and the mixture of the threeaqueous fractions (water extracts) were collected and analyzed as shownin Table 11.

TABLE 11 Extraction of crude biodiesel with water (three stages) at27.5° C. A:O mass ratio of 0.05 at each stage. Glycerin Water FeedRaffinate Extracts Biodiesel 80.1 94.6 0.1 Triacetin 12.6 5.1 30.5Diacetin 5.9 0.1 22.7 Monoacetin 0.9 0.0 3.9 Glycerol 0.5 0.0 2.1 Water0.0 0.2 40.7

Example 11: Absorption of CO₂ into an Ionic Liquid

The following experiments are modeled from published conceptualexperiments which utilized the same process solutions for the notedabsorptions. The noted data is the same as the published conceptualexperiments on the presumption that similar if not better results willbe achieved using a fiber conduit contactor. Ionic liquid1-n-butyl-3-methylimidazolium acetate [bmim][Ac] was pumped at 1 mL/minover the fibers as a constrained phase in a ½′ by 12″ fiber conduitcontactor. CO₂ flowed through the free volume of the reactor at 100 kPaand 30° C. CO₂ absorption by the ionic liquid resulted in a weightincrease (wt %) of 13.3%. Similar experiments with MEA and MEA:H₂O(50:50 vol) resulted in weight increases of 0.9% and 12%, respectively.

What is claimed:
 1. A method of chemical extraction, comprising:introducing a first stream comprising an extractant proximate aplurality of fibers positioned longitudinally within a conduit contactorand extending proximate to one or more collection vessels, wherein thefirst stream constitutes a phase substantially constrained to exteriorsurfaces of the fibers; introducing a second stream into the conduitcontactor proximate to the plurality of fibers, wherein the secondstream constitutes a phase flowing in alignment and between the fibersthat is in contact with and is substantially immiscible with the firststream, wherein the second stream is a fermentation broth or a wastestream from a fermentation process, and wherein the first stream and thesecond stream are introduced into the conduit contactor such that theextractant of the first stream interacts with the second stream toextract a fermentation product and/or a fermentation byproduct from thesecond stream into the first stream; receiving the first and secondstreams in the one or more collection vessels; and withdrawingseparately the first and second streams from the one or more collectionvessels.
 2. The method of claim 1, wherein the first stream and thesecond stream are introduced into the conduit contactor such that theextractant of the first stream interacts with the second stream toextract an alcohol from the second stream into the first stream.
 3. Themethod of claim 2, wherein the alcohol is butanol.
 4. The method ofclaim 2, wherein the second stream is an aqueous stream comprising lessthan 1.5% butanol.
 5. The method of claim 1, wherein the first streamand the second stream are introduced into the conduit contactor suchthat the extractant of the first stream interacts with the second streamto extract an acid from the second stream into the first stream.
 6. Themethod of claim 5, wherein the acid is lactic acid.
 7. The method ofclaim 5, wherein the acid is tartaric acid, succinic acid, acetic acidor malic acid.
 8. The method of claim 1, wherein the extractant is anionic liquid.
 9. The method of claim 8, wherein the extractant is a roomtemperature ionic liquid.
 10. A method of dye extraction, comprising:introducing a first stream comprising an extractant proximate aplurality of fibers positioned longitudinally within a conduit contactorand extending proximate to one or more collection vessels, wherein thefirst stream constitutes a phase substantially constrained to exteriorsurfaces of the fibers; introducing a second stream comprising a dyeinto the conduit contactor proximate to the plurality of fibers, whereinthe second stream constitutes a phase flowing in alignment and betweenthe fibers that is in contact with and is substantially immiscible withthe first stream, and wherein the first stream and the second stream areintroduced into the conduit contactor such that the extractant of thefirst stream interacts with the second stream to extract the dye fromthe second stream into the first stream; receiving the first and secondstreams in the one or more collection vessels; and withdrawingseparately the first and second streams from the one or more collectionvessels.
 11. The method of claim 10, wherein the dye is an azo dye. 12.The method of claim 10, wherein the second stream is an aqueous stream.13. The method of claim 10, wherein the extractant is an ionic liquid.14. The method of claim 13, wherein the extractant is a room temperatureionic liquid.
 15. A method of chemical extraction, comprising:introducing a first stream comprising an extractant proximate aplurality of fibers positioned longitudinally within a conduit contactorand extending proximate to one or more collection vessels, wherein thefirst stream constitutes a phase substantially constrained to exteriorsurfaces of the fibers; introducing a second stream comprising apharmaceutical compound into the conduit contactor proximate to theplurality of fibers, wherein the second stream constitutes a phaseflowing in alignment and between the fibers that is in contact with andis substantially immiscible with the first stream, and wherein the firststream and the second stream are introduced into the conduit contactorsuch that the extractant of the first stream interacts with the secondstream to extract the pharmaceutical compound from the second streaminto the first stream; receiving the first and second streams in the oneor more collection vessels; and withdrawing separately the first andsecond streams from the one or more collection vessels.
 16. The methodof claim 15, wherein the pharmaceutical compound is ibuprofen.
 17. Themethod of claim 15, wherein the pharmaceutical compound is anantibiotic.
 18. The method of claim 15, wherein the second stream is amanufacturing broth used to create the pharmaceutical compound.
 19. Themethod of claim 15, wherein the extractant is an ionic liquid.
 20. Themethod of claim 19, wherein the extractant is a room temperature ionicliquid.